"BTW, learning Kubernetes can be done in a few days. " - Learn something in a few days and the ability to run it in production are completely 2 different things. Security, upgrades and troubleshooting cannot be learned in couple of days.
Anyone who starts doing anything "in production" based on a "maybe you don't need k8s" article should step back and think about whether they are the right person to put things into production.
Are you bootstrapping your stealth-mode side-project? Pick whatever you think is best, but think about the time value of operations. (So maybe just pick a managed k8s.)
Are you responsible for a system that handles transactions worth millions of dollars every day? Then maybe, again you should seek the counsel of professionals.
Otherwise these articles are just half-empty fuel cans for an (educated?) dumpster fire.
That said HashiCorp stuff is almost guaranteed to be amazing. I haven't even looked at Nomad, but I think anybody starting out with orchestration stuff should give it a go, and when they think they have outgrown it they will know what's next. Maybe k8s, maybe something else.
Sure, but "how to toss existing docker containers into GKE" is IMO less than three days. Unless you have a reason to manage your own k8s cluster, k8s is extremely easy.
